on my 2001 chevy 2500hd 8.1L iv been having some starting problems i think its the fuel pump so far if put in a new fuel filter and changed the spark plugs 93k miles on the truck. but i came across some info saying these trucks had issues with the crank position sensor. iv noticed when cranking when it does not start that nothing is registering on the tach. do these trucks normally get a tach signal while cranking or could a crank position sensor be my problem.